Caption: Ciliate protozoan (Stylonychia sp.) dividing by binary fission, light microscopy. Binary fission involves one of the single-celled Stylonychia dividing into two, which become independent organisms. Stylonychia inhabits freshwater and moist soil throughout the world, feeding on bacteria and other small micro-organisms. It moves by beating the cilia (hair-like extensions) on its body. The cilia around its mouth are also used to waft prey towards it. Filmed with darkfield illumination.